The Lib Dems are going to be hard pressed to influence future policy at all unless there is another hung parliament. It may sound like a bad joke, ghoti, but we've got to start somewhere.
The other parties:
Labour party policy: fine words, zero detail.
Tories: fine words, but details more about saving money for consumers than saving the environment.
UKIP's policy is allegedly (it's a 404)
a bit of a disaster.